The development of Micro-Electro-Mechanical Systems (MEMS) technology has enabled manufacturers to produce inertial sensors (e.g., accelerometers) of sufficiently small size, cost, and power consumption to fit into portable electronic devices. Such inertial sensors can be found in a limited number of commercial electronic devices such as cellular phones, portable music players, pedometers, game controllers, and portable computers.
Step counting devices (e.g., pedometers) are used to monitor an individual's daily activity by keeping track of the number of steps that he or she takes. Steps are counted by sensing accelerations caused by user motion. Step counting devices are not able to detect or count motions other than steps. Nor are step counting devices capable of differentiating between different user activities.
Some step counting devices may be attached to and receive input from external sensors (e.g., a bike cadence sensor) to detect a motion other than a step. However, such step counting devices rely on external sensors for such monitoring capability. These devices are not capable of detecting or counting motions other than steps without the input from external sensors.